Webb discovers unexpected phenomena above Jupiter's Great Red Spot

using James Webb Space TelescopeScientists have noticed the area above. JupiterDiscover a previously unseen array of features in the Sun's Great Red Spot. The region, previously thought to be largely unremarkable, hosts a variety of complex structures and activities.

Recent observations by the Webb telescope have revealed surprising details about Jupiter’s upper atmosphere, particularly over the Great Red Spot, revealing complex structures influenced by gravitational waves. These findings, captured using the high-resolution capabilities of the Webb telescope, could support the Jupiter Icy Moons (Juice) mission, furthering our understanding of Jupiter and its moons.

Jupiter's atmosphere revealed

Jupiter is one of the brightest objects in the night sky, easily visible on clear nights. Aside from the bright northern and southern lights at the planet’s polar regions, the glow from Jupiter’s upper atmosphere is faint and therefore challenging for ground-based telescopes to discern details in this region. However, the Webb Observatory’s infrared sensitivity allows scientists to study Jupiter’s upper atmosphere above the infamous Great Red Spot in unprecedented detail.

Jupiter's upper atmosphere is the interface between the planet's magnetic field and its underlying atmosphere. Here, one can see the bright, vibrant displays of the northern and southern lights, fueled by volcanic material ejected from Jupiter's moon Io. However, as one approaches the equator, the structure of the planet's upper atmosphere is affected by incoming sunlight. Because Jupiter receives only 4 percent of the sunlight that Earth does, astronomers expected this region to be homogeneous in nature.

Jupiter’s Great Red Spot was observed by Webb’s Near Infrared Spectrometer (NIRSpec) in July 2022, using the instrument’s integrated field capabilities. The early release team’s observations sought to investigate whether this region was actually faint, and the region above the famous Great Red Spot was targeted for Webb’s observations. The team was surprised to find that the upper atmosphere hosted a variety of complex structures, including dark arcs and bright spots, across the entire field of view.

Webb NIRSpec observations show infrared light emitted by hydrogen molecules in Jupiter’s ionosphere. These molecules are more than 300 kilometers above the storm clouds, where sunlight ionizes the hydrogen and triggers infrared emission. In this image, the reddest colors show hydrogen emission from these high altitudes in the planet’s ionosphere. The bluest colors show infrared light from lower altitudes, including cloud tops in the atmosphere and the very prominent Great Red Spot.
Jupiter is far from the Sun, and thus receives a low and uniform level of daylight, meaning that most of the planet’s surface is relatively dim at these infrared wavelengths—especially compared to the emission of particles near the poles, where Jupiter’s magnetic field is particularly strong. Contrary to what researchers expected, this region would appear homogeneous in nature, it hosts a variety of complex structures, including dark arcs and bright spots, across the entire field of view.
Copyright: ESA/Webb, NASA and CSA, H. Melin, M. Zamani (ESA/Webb)

Amazing Discoveries Above the Great Red Spot

“We thought this region, perhaps naively, would be really boring,” said Henrik Melin, team leader from the University of Leicester in the United Kingdom. “It's actually as interesting as the northern lights, if not more interesting. Jupiter never ceases to surprise us.”

Although the light emitted from this region is driven by sunlight, the team suggests that there must be another mechanism that is changing the shape and structure of the upper atmosphere.

“One way this structure can be changed is through gravity waves – which are like waves hitting a beach, creating ripples in the sand,” Henrik explained. “These waves are generated deep in the turbulent lower atmosphere, around the Great Red Spot, and can travel to high altitudes, changing the structure and emissions of the upper atmosphere.”

Observations and future implications

The team explains that these atmospheric waves can sometimes be detected on Earth, but they are much weaker than those Webb observed on Jupiter. The team also hopes to conduct subsequent Webb observations of these complex wave patterns in the future to investigate how the patterns move within the planet’s upper atmosphere and improve our understanding of the energy budget in this region and how the features change over time.

These results may also support ESA's Jupiter Icy Moons Explorer, Juice, which launches on April 14, 2023. Juice will make detailed observations of Jupiter and its three large ocean-bearing moons – Ganymede, Callisto and Europe – Using a suite of remote sensing, geophysical, and in-situ instruments, the mission will characterize these moons as potential planetary bodies and habitats, explore Jupiter’s complex environment in depth, and study the broader Jupiter system as a prototype for gas giant planets throughout the universe.

Reflections on the Impact of Research

These observations were made as part of Early Science Program No. 1373: ERS observations of Jupiter as evidence of JWST's capabilities in solar system science (Co-investigators: I. de Pater, T. Fouchet).

“This ERS proposal was written in 2017,” shared team member Imke de Pater from University of California, Berkeley“One of our goals was to investigate why the temperature above the Great Red Spot was so high, as recent observations at the time showed. NASA “The Infrared Telescope Facility revealed this. However, our new data showed completely different results.”

These results were published in Natural astronomy.

Reference: “Ionospheric irregularities at Jupiter observed by the James Webb Space Telescope” by Henrik Melin, J. O’Donoghue, L. Moore, T. S. Stallard, L. N. Fletcher, M. T. Roman, J. Harket, O. R. T. King, M. Thomas, R. Wang, P. A. Teranti, K. L. Knowles, E. D. Pater, T. Fouché, P. H. Fry, M. H. Wong, P. J. Holler, R. Hueso, M. K. James, J. S. Orton, E. Mora, A. Sanchez-Lavega, E. Lelouch, K. D. Claire, M. R. Showalter, 21 June 2024. Natural astronomy.
DOI: 10.1038/s41550-024-02305-9

Webb is the largest and most powerful telescope ever launched into space. Under an international cooperation agreement, ESA provided the telescope launch service, using an Ariane 5 launch vehicle. In collaboration with partners, ESA was responsible for the development and qualification of the Ariane 5 modifications for the Webb mission and for the procurement of the launch service by Arianespace. ESA also provided the NIRSpec spectrograph and 50% of the mid-infrared instrument. Marywhich was designed and built by a consortium of nationally funded European institutes (the European MIRI Consortium) in partnership with Jet Propulsion Laboratory And the University of Arizona.

Webb is an international partnership between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).